Conventionally, as set forth in JP-A-2013-44178, flush toilets have been known wherein in a wash-down type of flush toilet wherein a gravity fed storage tank is disposed as a water supply apparatus at the rear top portion of a flush toilet, the inside perimeter surface of the rim portion is formed to rise in an essentially plumb direction, and flush water is spouted from a rim spout port formed in the front region, to perform a flush as it circulates over the interior of the bowl portion.